Update fstab.postinstall documentation in gen_build_prop.py

Update the documentation for the ro.postinstall.fstab.prefix
property to reflect that the default is /system.

Bug: None
Change-Id: Ia03c07cef31b03346cbabbb48e661c0c63aa6317
Test: None

1 files changed, 9 insertions, 1 deletions

diff --git a/scripts/gen_build_prop.py b/scripts/gen_build_prop.py
index 430e6134a..355f33d6c 100644
--- a/scripts/gen_build_prop.py
+++ b/scripts/gen_build_prop.py
@@ -308,7 +308,15 @@ def append_additional_system_props(args):
     props.append(f"ro.sanitize.{sanitize_target}=true")
 
   # Sets the default value of ro.postinstall.fstab.prefix to /system.
-  # Device board config should override the value to /product when needed by:
+  #
+  # Device board configs can override this to /product to use a
+  # product-specific fstab.postinstall file (installed to
+  # /product/etc/fstab.postinstall). If not overridden, the
+  # system/extras/cppreopts/fstab.postinstall file (installed to
+  # /system/etc/fstab.postinstall) will be used.
+  # Note: The default fstab.postinstall is generic and may be slower
+  # because it tries different mount options line by line to ensure
+  # compatibility across various devices.
   #
   #     PRODUCT_PRODUCT_PROPERTIES += ro.postinstall.fstab.prefix=/product
   #